Traditional inductive heating systems utilize a resonant frequency power supply which delivers a sinusoidal current at a resonant frequency to the heater coil. In such systems, in order to increase the heating power delivered to the load, a large current must be delivered to the heater coil. There are numerous problems generated by the use of such large currents, including large power losses in the switching circuit, parasitic heating of the coil, the necessity for large tank capacitors (for tuning the resonance circuit), and the complexity of the control circuit. Most notably, such systems deliver to the load a sinusoidal resonant frequency current which signal is a continuous function of time.
It would be desirable to provide a power supply for an inductive heating system which is flexible and controllable to enable delivery of a desired rate of inductive heating and/or which is more efficient than the known inductive heating power supplies. Preferably, such a system would avoid one or more of the problems of complexity, failure, and cost of the prior known power supplies.